#sphere {
    position: absolute;
    z-index: 100;
    width: 100%;
    height: 100%;
    text-align: center;
    font-size: 32px;
  }
  
  #sphere-button {
    position: absolute;
    z-index: 100;
    width: 100%;
    bottom: 50px;
    text-align: center;
    margin: 0 auto;
    font-size: 32px;
  }
  
  .start {
    /* 居中 */
    display: flex;
    justify-content: center;
  }
  
  .btn-start {
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 208px; /* 13rem -> 208px */
    overflow: hidden;
    height: 48px; /* 3rem -> 48px */
    background-size: 300% 300%;
    backdrop-filter: blur(16px); /* 1rem -> 16px */
    border-radius: 80px; /* 5rem -> 80px */
    transition: 0.5s;
    animation: gradient_301 5s ease infinite;
    border: double 4px transparent;
    background-image: linear-gradient(#212121, #212121),
      linear-gradient(
        137.48deg,
        #ffdb3b 10%,
        #fe53bb 45%,
        #8f51ea 67%,
        #0044ff 87%
      );
    background-origin: border-box;
    background-clip: content-box, border-box;
    -webkit-animation: pulsate-fwd 1.2s ease-in-out infinite both;
    animation: pulsate-fwd 1.2s ease-in-out infinite both;
  }
  
  .btn-cancel {
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 208px; /* 13rem -> 208px */
    overflow: hidden;
    height: 48px; /* 3rem -> 48px */
    background-size: 300% 300%;
    backdrop-filter: blur(16px); /* 1rem -> 16px */
    border-radius: 80px; /* 5rem -> 80px */
    transition: 0.5s;
    animation: gradient_301 5s ease infinite;
    border: double 4px transparent;
    background-image: linear-gradient(#212121, #212121),
      linear-gradient(
        137.48deg,
        #ffdb3b 10%,
        #fe53bb 45%,
        #8f51ea 67%,
        #0044ff 87%
      );
    background-origin: border-box;
    background-clip: content-box, border-box;
  }
  
  #sphere-stars {
    position: absolute;
    z-index: -1;
    width: 100%;
    height: 100%;
    overflow: hidden;
    transition: 0.5s;
    backdrop-filter: blur(16px); /* 1rem -> 16px */
    border-radius: 80px; /* 5rem -> 80px */
  }
  
  strong {
    z-index: 2;
    font-family: 'Avalors Personal Use';
    font-size: 12px;
    letter-spacing: 5px;
    color: #ffffff;
    text-shadow: 0 0 4px white;
  }
  
  #glow {
    position: absolute;
    display: flex;
    width: 192px; /* 12rem -> 192px */
  }
  
  .circle {
    width: 100%;
    height: 30px;
    filter: blur(32px); /* 2rem -> 32px */
    animation: pulse_3011 4s infinite;
    z-index: -1;
  }
  
  .circle:nth-of-type(1) {
    background: rgba(254, 83, 186, 0.636);
  }
  
  .circle:nth-of-type(2) {
    background: rgba(142, 81, 234, 0.704);
  }
  
  .btn-start:hover #sphere-stars {
    z-index: 1;
    background-color: #212121;
  }
  
  .btn-start:hover {
    transform: scale(1.1);
  }
  
  .btn-start:active {
    border: double 4px #fe53bb;
    background-origin: border-box;
    background-clip: content-box, border-box;
    animation: none;
  }
  
  .btn-start:active .circle {
    background: #fe53bb;
  }
  
  #stars {
    position: relative;
    background: transparent;
    width: 3200px; /* 200rem -> 3200px */
    height: 3200px; /* 200rem -> 3200px */
  }
  
  #stars::after {
    content: '';
    position: absolute;
    top: -160px; /* -10rem -> -160px */
    left: -1600px; /* -100rem -> -1600px */
    width: 100%;
    height: 100%;
    animation: animStarRotate 90s linear infinite;
  }
  
  #stars::after {
    background-image: radial-gradient(#ffffff 1px, transparent 1%);
    background-size: 50px 50px;
  }
  
  #stars::before {
    content: '';
    position: absolute;
    top: 0;
    left: -50%;
    width: 170%;
    height: 500%;
    animation: animStar 60s linear infinite;
  }
  
  #stars::before {
    background-image: radial-gradient(#ffffff 1px, transparent 1%);
    background-size: 50px 50px;
    opacity: 0.5;
  }
  
  .continue-buttons {
    display: flex;
    justify-content: center;
    .start:nth-of-type(2) {
      margin-left: 30px;
    }
  }
  
  @keyframes animStar {
    from {
      transform: translateY(0);
    }
  
    to {
      transform: translateY(-2160px); /* -135rem -> -2160px */
    }
  }
  
  @keyframes animStarRotate {
    from {
      transform: rotate(360deg);
    }
  
    to {
      transform: rotate(0);
    }
  }
  
  @keyframes gradient_301 {
    0% {
      background-position: 0% 50%;
    }
  
    50% {
      background-position: 100% 50%;
    }
  
    100% {
      background-position: 0% 50%;
    }
  }
  
  @keyframes pulse_3011 {
    0% {
      transform: scale(0.75);
      box-shadow: 0 0 0 0 rgba(0, 0, 0, 0.7);
    }
  
    70% {
      transform: scale(1);
      box-shadow: 0 0 0 10px rgba(0, 0, 0, 0);
    }
  
    100% {
      transform: scale(0.75);
      box-shadow: 0 0 0 0 rgba(0, 0, 0, 0);
    }
  }
  
  .btn-end {
    -webkit-animation: pulsate-fwd 0.9s ease-in-out infinite both;
    animation: pulsate-fwd 0.9s ease-in-out infinite both;
    cursor: pointer;
  }
  
  .btn-end {
    --glow-color: rgb(217, 176, 255);
    --glow-spread-color: rgba(191, 123, 255, 0.781);
    --enhanced-glow-color: rgb(231, 206, 255);
    --btn-color: rgb(100, 61, 136);
    border: 0.25em solid var(--glow-color);
    padding: 16px 48px; /* 1em 3em -> 16px 48px */
    color: var(--glow-color);
    font-size: 15px;
    font-weight: bold;
    background-color: var(--btn-color);
    border-radius: 16px; /* 1em -> 16px */
    outline: none;
    box-shadow: 0 0 1em 0.25em var(--glow-color),
      0 0 4em 1em var(--glow-spread-color),
      inset 0 0 0.75em 0.25em var(--glow-color);
    text-shadow: 0 0 0.5em var(--glow-color);
    position: relative;
    transition: all 0.3s;
    -webkit-animation: swing-in-top-fwd 0.5s
      cubic-bezier(0.175, 0.885, 0.32, 1.275) both;
    animation: swing-in-top-fwd 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275) both;
  }
  
  .btn-end::after {
    pointer-events: none;
    content: '';
    position: absolute;
    top: 120%;
    left: 0;
    height: 100%;
    width: 100%;
    background-color: var(--glow-spread-color);
    filter: blur(32px); /* 2em -> 32px */
    opacity: 0.7;
    transform: perspective(1.5em) rotateX(35deg) scale(1, 0.6);
  }
  
  .btn-end:hover {
    color: var(--btn-color);
    background-color: var(--glow-color);
    box-shadow: 0 0 1em 0.25em var(--glow-color),
      0 0 4em 2em var(--glow-spread-color),
      inset 0 0 0.75em 0.25em var(--glow-color);
  }
  
  .btn-end:active {
    box-shadow: 0 0 0.6em 0.25em var(--glow-color),
      0 0 2.5em 2em var(--glow-spread-color),
      inset 0 0 0.5em 0.25em var(--glow-color);
  }
  
  @-webkit-keyframes pulsate-fwd {
    0% {
      -webkit-transform: scale(1);
      transform: scale(1);
    }
  
    50% {
      -webkit-transform: scale(1.1);
      transform: scale(1.1);
    }
  
    100% {
      -webkit-transform: scale(1);
      transform: scale(1);
    }
  }
  
  @keyframes pulsate-fwd {
    0% {
      -webkit-transform: scale(1);
      transform: scale(1);
    }
  
    50% {
      -webkit-transform: scale(1.2);
      transform: scale(1.2);
    }
  
    100% {
      -webkit-transform: scale(1);
      transform: scale(1);
    }
  }
  
  @-webkit-keyframes tracking-in-expand-fwd {
    0% {
      letter-spacing: -8px; /* -0.5em -> -8px */
      -webkit-transform: translateZ(-700px);
      transform: translateZ(-700px);
      opacity: 0;
    }
  
    40% {
      opacity: 0.6;
    }
  
    100% {
      -webkit-transform: translateZ(0);
      transform: translateZ(0);
      opacity: 1;
    }
  }
  
  @keyframes tracking-in-expand-fwd {
    0% {
      letter-spacing: -8px; /* -0.5em -> -8px */
      -webkit-transform: translateZ(-700px);
      transform: translateZ(-700px);
      opacity: 0;
    }
  
    40% {
      opacity: 0.6;
    }
  
    100% {
      -webkit-transform: translateZ(0);
      transform: translateZ(0);
      opacity: 1;
    }
  }
  